Bronze mixer and conditioner



Oct. 1, 1940.

C. K. HERCHER BRONZE MIXER AND CONDITIONER Filed Oct. 15, 1939 1&-

m I as n 28 Patented Oct. 1, 1940 UNITED STATES PATENT OFFICE BRONZEMIXER AND CONDITIONER Charles K. Hercher, Milwaukee, Wis.

Application October 16, 1939, Serial No. 299,580

3 Claims.

This invention relates to improvements in mixing and conditioningdevices and While not limited thereto is particularly applicable to themixing, sifting, and conditioning of bronzes used for remove the lumpsand impurities, while at the same time adding fresh powder. The lattershould be intimately mixed with the old powder so as to avoid anydifference in color throughout the mass of the powder resulting fromstratification of the discolored and fresh powder. The

mixing has heretofore been done by hand as no suitable apparatus wasavailable. Hand mixing, however, has many disadvantages, some of whichare the following:

The individual powder particles are of a flaky nature and the intimatemixing of such flaky material into a homogeneous mass isextremelydifiicult and time-consuming.

The mixing of the powder disperses some of it. The powder dusts areirritating to the operator and often dangerous to his health and thehealth of other occupants of a room filled with suspended powder.

The suspended powder in the room floats into the lithographing apparatusand injures it and often spoils work which is being printed or which isstored in the room.

An appreciable amount of powder is lost by dispersion in the room bymanual mixing and sifting.

The present invention eliminates the aforementioned and otherdifficulties and affords a thorough sifting and mixing of the powders torestore them to their highest quality and usefulness.

An object of the invention is to provide a process and a machine whichintimately mixes powders of different quality into a homogeneous masswhile the powders are dispersed or suspended in air or another gas. 7

Another object is to provide a machine which efliciently removesimpurities and lumps from powders.

Another object is to provide a method and a machine which is dust tightand thus protects the-operators from inhaling powder dust.

Another object is to provide a method and a machine which is rapid inoperation.

Another object is to provide a machine in which the mixed powder can bestored and protected until it is needed.

Another object is to provide a power operated machine of theaforementioned character.

Another object is to provide a machine which is compact and easilytransported from one place to another.

Another object is to provide a machine which requires a minimum ofattention.

Other objects and advantages will hereinafter appear.

The machine comprises a vided into an upper and a lower compartment.Mounted in the upper compartment is an oscillatable basket having afinely perforated wall and adapted to receive the powders to be mixedand screened. 'Iherebelow the upper compart- T;

ment is provided with an agitator having revolving arms or paddles,which agitate and mix the screened powder. The powder which settles inthe compartment can be released into a pan in the bottom compartment ofthe cabinet by the opening of a slide in the lower part of said uppercompartment. A motor is geared to the shaft of the agitator to revolvethe same, while the basket is pivotally supported on a second shaftwhich is connected to the first mentioned shaft by a connecting rod andcrank in such a manner that upon rotation of said agitator by the motor,the basket is oscillated forth and back to agitate the powder therein tothereby mix it and pass it through the perforations inthe basket intothe lower part of the upper compartment.

The accompanying drawing is illustrative of an embodiment of theinvention.

In the drawing, Figure l is a vertical section through the machineparallel with the operating shafts.

Fig. 2 is a transverse vertical section along the line 22 of Fig. 1,while Fig. 3 is a vertical section along the line 3-3 of Fig. 1.

Referring to the drawing the machine comprises a frame or cabinet Iwhich is provided with a top door 2, hinged to the body of the cabinetby means of hinges 3 and further provided with flanges 4 which fitclosely over the outside of the cabinet. To make the door 2 completelydust tight, a packing strip of felt 5 or other suitable material isattached to the inside surface of the door 2 in a manner to engage thetop edge of the cabinet. The cabinet is also produst tight cabinet di- 1vided at its lower part with a hinged door. 6 the purpose of which willbe explained hereafter.

A screening basket or shaker i of rectangular shape is supported by ashaft 8 which passes through its side walls 9 and it) to which it isfastened by means of flanges l i and i2 respectively, and the shaft inturn is pivotally supported in bearings l3 and H3 respectively, thelatter being attached to two opposite sides of the cabinet i. One end ofthe shaft extends beyond the bearing l3 and has attached thereto a leveror crank E5. The bottom of the basket I is provided with a screen it ofsuitable fineness for passing the powder.

Mounted in the cabinet i below the basket 7 is a semicircular wall I?which with two sides of the box forms a mixing chamber having asubstantially semi-cylindrical bottom for reception of the powderdropping through the screen it. A rotatable shaft I8 is pivotallymounted in bearings I9 and 28 fastened to opposite side walls of thecabinet. The shaft I8 is parallel to the shaft 8 and substantiallycoaxial with the central axis of the wall H. The shaft 58 is providedwith a series of radial rods or paddles 2! preferably comprising wiresextending close to the surface of the wall H and having their ends atone side of the center connected with a cross wire 22, which enhancesthe stirring action of said paddles. The shaft [8 is extended outside ofthe cabinet beyond the bearing i9 and has keyed thereto a gear 23 whichmeshes with a pinion 2d of a driving motor 25. The gear 23 is providedwith an eccentric pin 26 on which is pivotally mounted a connecting rod21, the other end of which engages the crank !5, the arrangement beingsuch that as the gear 23 rotates it oscillates the shaft 8 through themedium of the connecting rod 2?.

The motor 25 is mounted on a base plate 28 which in turn is supportedfrom the cabinet 11 by suitable brackets 29. A cover 30 which isattached to the cabinet i and base plate 28 encloses the motor andgearing.

The cabinet is arranged to receive a receptacle 3| which can be insertedthrough the door ii and which is employed when it is desired to withdrawfinished powder from the cabinet. For this purpose the lower centralpart of the wall H is provided with a slide 32 which passes through adust tight slot 33 in one wall of the cabinet and which is providedoutside thereof with an operating handle 34.

To enhance the shaking effect of the oscillation of the basket '7, thecabinet may be provided with adjustable abutments which engage thebasket 1 as it approaches its limits of travel to produce an impactthereon which causes the powder to more readily pass through the screenit. The resiliency of the basket and the lost motion of the variouspartsare sufiicient to prevent any injurious strains-on the parts whenthe basket engages the stops 35. The impact referred to may also besupplied by providing a lost motion, for instance, in the connectionbetween the rod 2'! and the crank i5.

llf it is desired to screen used powder and/or mix it with new powder,the respective material is placed into the basket 1 and the cover 2 isclosed, whereupon the motor 25 is started. Thereupon the basket i isshaken and the powder therein is thoroughly mixed and gradually passesthrough the screen 16 into the upper compartment where it is furtheragitated and mixed by the rotating paddles 2!. In addition, due to theturbulence of the air created by the paddles the particles as they passfrom the screen I6 are for some time held in suspension and thus arefurther mixed by the action of the paddles and of the turbulent air.

After the powder has been mixed it may be withdrawn by the opening ofthe slide 32 whereupon it drops into the pan 3 I. The entire processtakes place in the dust tight cabinet and no powder can escape andinjure the workmen or the work. All foreign matter in the used powder isretained on the screen 56, while all lumps are thoroughly broken upbefore the particles can pass through the screen. The labor required isa minimum, as it is only necessary to place the powder into the basketafter which the motor is started and the entire operation thereafter isautomatic and requires no further attention. The entire apparatus, beingcompact and self contained, may be easily moved where it is needed.

It is of course possible to replace the motor by hand operating means. Ido not wish to limit myself to the embodiment of the inventionillustrated and described in the present application, but claim allobvious modifications thereof coming within the scope of the appendedclaims.

What I claim as new and desire to secure by Letters Patent is:

l. A casing enclosing an air tight chamber, a receptacle disposed in theupper part of said chamber and oscillatable to sift bronze printingpowder through a sieve at its bottom, an agitator disposed in saidchamber below said receptacle and rotatable to agitate the air fordelaying the settling of the powder passing through said sieve andthereby pro-long its exposure to the air, and means to simultaneouslyrotate said agitator and oscillate said receptacle.

2. A casing enclosing an air tight chamber having a concave,substantially semi-circular bottom, a receptacle disposed in the upperpart of said chamber having a perforate screening wall and oscillatableabout a horizontal axis to sift metal printing powder through said wall,an agitator disposed in said chamber below said receptacle, providedwith radial paddles and rotatable about an axis substantially concentricwith said bottom to agitate the air in said chamber for delaying thesettling of the powder passing through said wall and thereby prolong itsexposure to the air, and means to simultaneously rotate said agitatorand to oscillate said receptacle.

3. A casing enclosing an air tight chamber having a concave,substantially semi-circular bottom, a receptacle disposed in the upperpart of said chamber having a perforated screening wall and a shaft foroscillation thereof about a horizontal axis tosift metal printing powderthrough said wall, an agitator disposed in said chamber below saidreceptacle, provided with radial paddles and with an agitator shaft toafford rotation about an axis substantially concentric with said bottomto agitate the air in said chamber for delaying the settling of thepowder passing through said wall and thereby prolong its exposure to theair, bearings for said shafts attached to said casing, a motor, adriving connection between said motor and said agitator shaft to rotatethe latter in accordance with the rotation of said motor, and aconnection between said agitator shaft and said receptacle shaft adaptedto'oscillate said receptacle simultaneously with the rotation of saidagitator.

. CHARLES K. HERCI-IER.

